FUNCTIONS OF MALE AND FEMALE. 



103 



the passive agent in copulation, merely receiving the semen of the 

 mule ; the female possesses material from which the offspring 



PIG. 97 1. Male of Aphis platanoides. c, ocelli ; llr, honey tubes ; P, copulatory organ. 



develop, and accordingly takes care of the development of the 

 fertilised egg and of the later fate of the offspring. Hence 

 the female usually possesses a 

 less active body and numerous 

 arrangements for the protection 

 and nourishment of her offspring, 

 which develop either from eggs 

 laid by the mother and sometimes 

 carried about with her, or in the 

 maternal body and are born alive. 

 The function of the male is to 

 seek, to excite, and to hold the 

 female during copulation ; hence, 

 as a rule, he possesses greater 

 vigour and power of movement, 

 higher development of the senses, 

 various means of exciting sexual 

 feeling, such as brighter colour- 

 ing, louder and richer voice, pre- 

 honsile organs, and external organs for copulation (fig. 97, a, b). 

 In exceptional cases, the functions relating to the maintenance of 



Rr 



FIG. 97i, Apterous oviparous female of the 

 same. 



